The health benefits of Vitamin D and the health consequences of its depletion are many. Basically, vitamin D improves skin immune function. Under the influence of vitamin D, generated by sunlight, the immune system activates the migration of T cells to the skin. In fact, a recent study demonstrated similar effects of topical vitamin D, as well as an anti-inflammatory effect. Other studies show the photoprotective effects of vitamin D analogs and calcitriol (the main metabolite of vitamin D) by a reduction in UV induced DNA damage.